INCIDENCE AND DAMAGE SEVERITY OF CHEWING INSECT PESTS AND FRUIT FLY ON BOTTLE GOURD AND THEIR MANAGEMENTS

Abstract

The experiment was conducted in the central farm of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka during the period from September, 2017 to May, 2018 to assess the incidence and damage severity of chewing insect pests and fruit fly on bottle gourd and their managements. BARI Lau 4 were used as the test crop for this study. The experiments consists of different management practices as treatment and they were T 1 : Mechanical and Cultural practices at 7 days interval, T 2 : Field sanitation + Spraying Sevin 85 SP @ 1.5 g/L of water at 7 days interval, T 3 : Spraying Folithion 50 EC @ 1.12 ml/L of water at 7 days interval, T 4 : Mechanical control + Spraying Rogor 40 L @ 1.0 ml/L of water at 7 days interval, T 5 : Spraying Dizol 60 EC @ 1.0 ml/L of water at 7 days interval, T 6 : Field sanitation + Spraying Proclaim 5 SG @ 1.0 g/L of water at 7 days interval and T 7 : Untreated control. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. Red pumpkin beetle, epilachna beetle, green leaf eating caterpillar, cutworm, grasshopper and fruit fly were observed during the study period. At vegetative and reproductive stage, the lowest leaf infestation (3.49% and 5.38%) was observed from T 4 treatment, whereas the highest infestation (15.56% and 15.02%) in T 7 treatment. In number and weight basis at early, mid and late fruiting stage the lowest fruit infestation (2.67% and 4.40%, 2.22% and 5.97%, 3.13% and 5.13%) was observed from T 4 treatment, whereas the highest infestation (10.65% and 10.53%, 10.15% and 16.24%, 11.92% and 14.54%) in T 7 treatment. The highest healthy fruit yield (69.96 t/ha) was recorded from T 4 , whereas the lowest (57.32 t/ha) from T 7 treatment. From the above findings it can be concluded that among the treatments, T 4 (Mechanical control + Spraying Rogor 40 L @ 1.0 ml/L of water at 7 days interval) may be revealed as the best treatments in respect of higher healthy fruit yield by reducing leaf and fruit infestation of bottle gourd.